1. Field of the Invention
The present invention relates to an infrared ray generating apparatus for use with a cable mouse for allowing a cable box that receives for example a cable TV program to be controlled using a VCR and an operation designating system for use with an electronic apparatus for allowing a cable box that receives a cable TV program to be controlled using a VCR.
2. Description of the Related Art
When a cable TV program is received, a cable box is used. The cable box has a tuner circuit that selects a desired channel and a decode circuit that demodulates and decodes output from the tuner circuit. The cable box is usually supplied by a cable TV company with which the user has a subscription contract. Thus, the specifications of cable boxes can vary from company to company. By connecting a cable box to a TV receiver, a picture signal transmitted through a cable is received by the TV receiver.
When the cable box is connected to the TV receiving a receive channel is selected by a tuner circuit in the cable box. Thus, it is difficult to reserve a program with a VCR. In other words, when a program is reserved by the VCR, a channel is designated by a tuner in the VCR. However, when the cable box is connected to the TV receiver, a channel cannot be designated by the tuner in the VCR when the cable box is connected to the TV receiver. Thus, a program cannot be reserved by the VCR.
To solve such a problem, a cable mouse is used. When the cable mouse is connected to the VCR and the cable mouse is positioned on an infrared ray receiving portion of the cable box, the cable box can be controlled by the VCR.
FIG. 6 is a schematic diagram showing an example of such an system. In FIG. 6, reference numeral 101 is a cable box. Reference numeral 102 is a VCR. Reference numeral 103 is a TV receiver. A cable mouse 104 is connected to the VCR 102. The cable mouse 104 is positioned on an infrared ray receiving portion 106 of the cable box 101. Reference numeral 106 is a commander that controls the VCR 102.
The cable box 101 is connected to a cable TV broadcasting station through a cable. The cable box 101 selects a desired channel and decodes a TV signal on the selected channel. The TV signal that is decoded by the cable box 101 is supplied to the VCR 102 and the TV receiver 103.
The cable mouse 104 is used to control the cable box 101 using the VCR 102. The cable mouse 104 is constructed as shown in FIG. 7. In FIG. 7, a command signal CMD10 is supplied from a microprocessor of the VCR 102 through an input terminal 111. The command signal CMD10 is supplied to a microprocessor 112 of the cable mouse 104. The microprocessor 112 converts the command signal CMD10 into a command signal CMD11 that is peculiar to the cable box 101. The command signal CMD11 is supplied to a light emitting diode 114 through a driver 113.
When a channel switching command signal is generated by the VCR 102, the command signal is supplied to the cable mouse 104. The microprocessor 112 of the cable mouse 104 converts the channel switching command signal into a channel switching command peculiar to the cable box 101. An infrared ray signal is generated by the light emitting diode 114 corresponding to the converted command signal. The generated infrared ray signal is received by the infrared ray receiving portion 105 of the cable box 101.
When the cable mouse 104 is connected to the VCR 102 and the cable mouse 104 is positioned on the infrared ray receiving portion 105 of the cable box 101, the cable box 101 can be controlled using the VCR 102. Thus, operations such as a program reserving operation can be performed by the VCR 102.
Related art references are U.S. Pat No. 5,151,789 and U.S. Pat. No. 5,123,046.
As described above, the command signal CMD10 supplied from the VCR 102 is converted into a command peculiar to the cable box 101 by the microprocessor 112 of the cable mouse 104. However, when all commands are converted and output by the microprocessor 112 of the cable mouse 104, it is difficult to change and add commands. In other words, whenever a command is changed or added, the microprocessor 112 of the cable mouse 104 needs to be newly developed and replaced.
Thus, an object of the present invention is to provide an infrared ray generating apparatus an operation designating system for use with an electronic apparatus that allows a command to be easily changed and updated.